1. Field of the Invention
The invention relates to comb polymers and a method of manufacturing same from macromonomers having a terminal double bond.
2. Discussion of the Prior Art
In the prior art, anionic oligomerization is recommended for synthesizing functional oligomers, particularly telechic oligomers with a narrow molecular weight distribution. In particular, with respect to monomers such as styrene, 1,3-butadiene, and isoprene, the literature describes manufacture of alpha,omega-bifunctional oligomers by initiation with bifunctional initiators and termination with suitable reagents. Macromonomers are suitable for a number of interesting applications, such as use as starting materials for the manufacture of comb polymers. (See Houben and Weyl, "Methoden der Organischen Chemie", 4th Ed., Vol. E20, pub. Georg Thieme, pp. 647-648, 1166-1167 (1987); Rempp, P. F., and Franta, E., Adv. Polym. Sci., 58, 1-3 (1984); and Mark, H. F., et al., "Encyclopedia of polymer science and technology", Vol. 9, pub. J. Wiley, pp. 195-204 (1987)). The unpublished Eur. Pat. App. 94-105,648.3 discloses the manufacture of comb polymers by radical copolymerization of
olefin-copolymer macromonomers of formula ##STR4## where R' represents hydrogen or methyl; PA1 R represents the organic group in an organolithium compound; PA1 [A] represents a segment formed by 1,4-addition of butadiene, optionally substituted with an alkyl group with 1-6 C atoms; PA1 [A'] represents a segment formed by vinyl addition of butadiene, optionally substituted with an alkyl group with 1-6 C atoms; and PA1 n and m each represent an integer from 10 to 3000; with PA1 (meth)acrylic acid esters of C.sub.1 -C.sub.26 -alkanols. PA1 (2) The sum of the parameters (a+b) equals 100 mol % of the monomers in the macromonomer of formula (I), wherewith a should be at most 80 mol %, or PA1 (3) The sum of b and c should equal 100 mol % of the monomers in the macromonomer of formula (I); and PA1 (4) If a is zero, R1 becomes R1', which represents an alkyl group with 2-18, preferably 2-10, particularly preferably 2-4 C atoms; PA1 (meth)acrylic acids of C.sub.1 -C.sub.28 -alkanols, PA1 functionalized, radically polymerizable monomers, PA1 vinyl esters of fatty acids, and PA1 vinylaromatic monomers. PA1 (meth)acrylic acids of C.sub.1 -C.sub.28 -alkanols, PA1 functionalized monomers, PA1 vinyl esters of fatty acids, and PA1 vinylaromatic monomers, such as styrene and C.sub.1 -C.sub.4 -alkylstyrenes. PA1 (meth)acrylic acid derivatives of formula (V) ##STR11## where PA1 functionalized monomers of formula (VI) in the amount of 0-75 wt. %, preferably 0.5-50 wt. %, particularly preferably 2-15 wt. %, based on the total weight of the monomers M ##STR12## where PA1 hydrogen or PA1 an alkyl group with 1-24 C-atoms, preferably 8-22 C atoms or PA1 alkyl-substituted alkyl groups, preferably phenyl groups having C.sub.1 -C.sub.18 -alkyl substituents, particularly preferably phenyl groups having C.sub.6 -C.sub.16 -alkyl substituents, where R8 and R9 each independently represent an alkyl group with 1-6 C atoms, or together with the nitrogen atom and possibly other hetero atoms represent a 5- or 6-membered heterocyclic ring; PA1 vinyl esters of formula (VII), in the amount of preferably 0-80 wt. %, particularly preferably 5-20 wt. %, of the total weight of the monomers M ##STR14## where R10 represents an alkyl group, optionally branched, with 1-13 C atoms; and PA1 vinylaromatics of formula (VIII), in the amount of preferably 0-60 wt. %, particularly preferably 0.5-40 wt. %, of the total weight of the monomers M ##STR15## where R11 and R12 represent hydrogen or an alkyl group with 1-4 C atoms. PA1 monomers of formula (VI) such as methyl methacrylate, 2-dimethylaminoethyl methacrylate, or butyl acrylate, as monomers M, and PA1 2-(4-morpholinyl)ethyl methacrylate or N-dimethylaminopropyl methacrylamide, as monomers of formula (VI). PA1 methanol, ethanol, propanol, pentanol, and isomers thereof, hexanol, and isomers thereof, cyclohexanol, methylcyclohexanol, 2-ethylhexanol, and PA1 higher aliphatic monohydric alcohols, such as isodecyl alcohol, isoundecyl alcohol, isotridecyl alcohol, fatty alcohols produced from natural raw materials, etc. PA1 alkoxylated phenols, e.g. based on phenol, alkyl-substituted phenols (e.g. tert-butylphenol and 2,6-dimethylphenol), isomeric mixtures and technical alkylphenols (comprising, e.g., octylphenol, nonylphenol, and/or dinonylphenol), PA1 naphthol, and alkyl-substituted naphthols. PA1 alkyl esters, substituted with at least one hydroxyl group, having 2-50 C atoms in the alkyl group, e.g., 2-hydroxyethyl (meth)acrylate, 2- and 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, or PA1 amides such as N-(2-hydroxyethyl)methacrylamide and N-(3-hydroxy-2,2-dimethylpropyl)methacrylamide. PA1 (meth)acrylic acid esters of amino alcohols, such as diethylaminoethyl (meth)acrylate, 2-(dimethylamino)propyl (meth)acrylate, 3-dimethylamino-2,2-dimethylpropyl (meth)acrylate, 2-tert-butylaminoethyl (meth)acrylate, 2(dimethylamino)ethoxyethyl (meth)acrylate, and PA1 corresponding amides, such as N-dimethylaminomethyl (meth)acrylamide, N-(3-dimethylamino)propyl (meth)acrylamide, N-(1-piperidinyl)methyl (meth)acrylamide, N-(3-morpholinylpropyl) (meth)acrylamide, 2-(1-imidazolyl)ethyl (meth)acrylate, N-methacryloyl-2-pyrrolidone, etc. PA1 the variant of case (2) (case 2') wherein b is 100 mol % (see Muehlhaupt, R., Nachr. Chem. Techn. Lab. (pub. VCH), 41., (12):1241-1351(1993)), or PA1 the variant of case 3' wherein c is 100 mol %, preferably produced by cationic polymerization of isobutylene.
wherein, R is contributed from the organolithium catalyst used in the anionic polymerization. Preferably R is a butyl or phenyl group.
Comb polymers comprised of a polyalkyl (meth)acrylate main chain and high molecular weight hydrocarbon side chains have extraordinary behavior in solutions, in addition to other technically interesting properties. The properties of such comb polymers suit them for use as viscosity index improving agents (V.I.-improvers) in the lubricants sector, as described, e.g., in the above-cited Eur. Pat. App. 94-105,648.3. (See Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A 15, pub. VCH, pp. 448-449 (1990)).
The macromonomers used according to the cited Eur. Pat. App. as starting materials for the comb polymers are produced on the basis of dienes. This route of synthesis comprises a hydrogenation step in addition to the polymerization and functionalization. It would be preferable to use a direct method of manufacturing saturated olefinic polymers having a reactive terminal group. Devising such a method is the underlying problem of the invention. In solving the problem, one advantageously exploits catalysis with metallocene catalysts (see Muehlhaupt, R., Nachrichten aus Chemie und Technik, 41, 1341 (1993)).